Answer:
The answer is B.
Explanation:
Subject-verb agreement means that subject and verb must agree in number. So, if the subject is in singular, the verb must also be in singular; if the subject is in plural, then the verb must also be in plural.
Let`s analyze these sentences (extracting subjects and verbs)
A. someone arrive - someone is singular (3rd person), so we need <em>-s</em> as a suffix ⇒ arrives
B. each of the students plans - plans refers to each which is singular
C. Judging people based on appearance are - judging is gerund which functions as a noun in singular, so the verb should have been is
D. Nick and Nora walks - these two people represents one subject as they are connected with conjunction and. If the conjunction was or, then Nick/Nora would be separate subjects and we could use the verb in the singular, which is not the case in the given sentence.
